Some communications devices (e.g., cellular phones) support two or more single subscriber identity modules (“SIMs” or “SIM cards”). SIMs are removable integrated circuits that securely store keys for subscriber identification, information regarding the cellular phone user (e.g., a unique cellular phone user number), a list of services for which the user has access, user passwords, and/or stored data for the user (e.g. a list of phone numbers). Thus, if a communications device supports two (or more) SIMs, the communications device can be configured to receive service (e.g., cellular service) from two (or more) different service providers, each service provider associated with a different SIM. For example, an owner of a communications device may receive service from a service provider for work-related phone service and service from a service provider for personal phone service. In some cases, each SIM is also associated with its own phone number specific to the service.
If a communications device is in idle mode, it can intermittently issue a “wake up” command at a predetermined period of time to check for incoming transmissions for a SIM. When a communications device supports dual SIMs, each of these SIMs is monitored for incoming transmissions (e.g., incoming cellular phone calls). Thus, if two or more SIMs are being monitored, the communications device consumes more battery power because it wakes up to check for incoming transmissions more often.
What is needed are systems and methods for reducing battery power consumption in a communications device having multiple SIMs.
Features and advantages of the present invention will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.